Vitamin A value of high beta‐carotene yellow maize in humans

Abstract

This study determined the vitaminA value of yellow maize β‐carotene in humans. Yellow maize was grown in a 23 atom% 2H2O cultural solution. Intrinsically labeled yellow maize β‐carotene showed the highest abundance of enrichment as[2H9] β‐carotene. Eight healthy men with mean age of 48.4±10, serum retinol concentration 59.2±17.l μg/dL, and BMI 22.4±3.1 volunteered and adhered to study diets. On day‐1 after a fasting blood sample draw, subjects consumed 300g of yellow maize porridge containing 1mg β‐carotene, 20g of fat and a blank oil capsule. On day‐8 a fasting blood sample was drawn, subjects consumed 1mg [13C10] retinyl acetate in oil capsule and 300g of white maize porridge with 20g of fat. Thirty six bloodsamples were collected from each subject over a span of 36‐days. Concentrations and enrichments of retinol and β‐carotenein dose and serum were determined by using HPLC, GC/MS and LC/MS.The AUC of retinol from yellow maize β‐carotene (1 mg) was 72.9nmole·d and the AUC of retinol 13C10 (1mg) was 161.1nmole·d. The conversion factor of yellow maize β‐caroteneto retinol was 2.7 ± 1.0 to 1 by weight. The conversion factor was negatively correlated with age and serum concentration of retinol (p<0.05). In eight healthy Zimbabwean men 1mg yellow maize β‐caroteneconsumed with 20 g fat has the same vitamin A activity as 0.37 mg retinol. (Funding: Nutricia Research Foundation and Pioneer Hi‐Bred International)